Only in part. Try telling "it was only a mild accusation" to the plaintiff. Better yet tell it to The Marines cos The Sailors will not piggin well believe it.
Well taking the piss out of the judiciary is never wise. There is no statute of limitations in UK.
What happened was the defendant changed his plea from not guilty to guilty . Join up the dots yourself but this is not the only case of it's kind. Plenty enough for dossier compilers to suffer from severe bouts of ring twitter and like Muhammed Ali once said "You can run but you can't hide". 
You know a lot more about the law than I do, but wasn't there the justification of something like "reasonable conclusion". Steve would have had some interaction with the person he was accusing. Had he presented his evidence rather than lying about what he had written would that have made a difference.
Looking this "Stevie Trap" up on YouTube he seems to have had a lot of success in setting up these stings.
Can you say a person was "grooming teenagers" in a text if you have reasonable grounds to believe that?